Stock exhaust, is it possible over time for the hangers to become loose say around the resonator and need tightening (05-06 hangers)

http://www.realoem.com/bmw/showparts...89&hg=18&fg=20

 

The short answer is yes, as any fastener has the possibility but more then likely no. My history with those hangers is once tight, they're a pain to remove. They are exposed to all the elements and will become progressively harder to loosen.

I take it you've got a rattle back there?

 

A MINI, rattle? Sounds almost like you think its a British car.



Yup, past 4k its that lovely vibration sound basting in the cabin, just from the resonator, and it looks to shake a bit much at idle in the driveway. I was hoping its at case of the nuts and bolts holding 5 and 11 together getting a little loose and figured tightening those two would be the easiest solution.

 

Well it's worth a try, but you also might want to go a little deeper and check the 2 large bolts holding the gas tank against the body. They'll be at the end of the straps just forward of the sway bar (I think) another owner was saying that after extensive searching he found those to be loose and they were the source of his vibration.

Now one for you: Ever heard of a vibration that only shows up when the headlights are on? I've got one that sounds like a knock-knock, but goes away when the headlights are turned off. I've stood next to the car and can't see of feel anything vibrating/rattling yet when you turn them off it goes away

 

Hmmm thats a good one, does it matter if the bonnet is open or closed? Do you have Xenons (could be washers getting stuck). Hmmm this one has me puzzled and my strongest uspoicion is something you don't want to hear.

 

I do have the xenons but like I said I don't feel anything in the there knocking. I hear it with both the hood closed and open. It sounds like it's coming from the passenger side - low. It does go away with rpm, which makes me think drive line, but the headlight aspect has me befuddled

 

Does it sound mechanical or electrical? Headlights work fine? I don't think anythign shares a fuse with the lights, so my suspicion was the BC1 sending a signal elsewhere, the fact it also goes away with RPM makes me think its something mechanical that is effected by the electrical system. If you put drain on the alternator does it come back (headlights off but say fan, A/C radio, dome light on) Although that sits right side high.

I'm going to go take a look at the hangers/tank bolts, if I can think of anything I'll add that when I get back.

 

Well gas tank was full but the right hanger there looked a little loose, couldn't quite tell about the resonator those hangers had a lot of bounce and looseness tot hem as well (about 2x the give as the muffler) I did get some clicking when I started up as well, but I'm writing it off as the fuel pumps fault. That PS fan is getting annoying, the MINI sat all day as soon as I started the engine the PS already needed to be cooled. Good thing shes going to the dealer soon. When I chat with my tech I'll see if he's encountered any such clicking before.

 

Thanks Drew, mine is deff mechanical. I'll be putting it on jacks tomorrow and having a good look see. The older PS motors really made a racket, I replaced mine about 30,000 miles ago and it's still very quite - nothing like the older version.

Sorry for the delay was off looking at property again

Thanks and keep that thinking cap on

 

Also look at the motor mount. Mine was just changed and the extra vibration noise I was chasing went away.

Also I once had a piece of gravel wedge between the heatshield and the resonator. Very annoying til I found it.

tim

 

Hey Tim,

Thanks for the ideas but the mount looks good, it's the old style, solid one and looks and feels good. I've also got the TSW Damper installed so not much movement there.

I've also checked allt he heat shields and we're good there.

The rock thing reminded my of our old 96 Mustang GT we had. One day it just started to transfer through the steering wheel, what would feel like one heck of a vibration. It would start after about 10 - 15 minutes of driving and then go away sometimes. Almost like it was misfiring, I thought plug wire split and opening up once the wire expanded due to the heat, but the going away part had me .

Turned out to be a large piece of gravel had become wedged between one of the fan blades and the shroud. The thermostat would call for the fan and the fan would drive this rock around the shroud, shaking the entire front end Took a bit to see it but it was one of these duh moments Of course my wife then admitted to hearing something loud bang and rattle around under the hood one day when she pulled into the drive

Still working on theory right now, but I might have an idea

 

I just got my vibration fixed, for me it was the hanger for the muffler. The weld for the hanger had gotten rusty and was vibrating at around 4k rpm. $47 dollars later at the muffler shop they tack welded it tight again. I saw it for the first time when I took my rear tire off jut started to pull away from the metal band its welded to. It doesnt sound like your cat but you can knock on it if its going bad you'll hear a rattle. Hope this helped out.

Ian

 

I had part of the hanger rust away, didn't start to rattle yet, i saw it when i changed my exhaust out, but it was definitely rusted in half. That may be where your problem lies as well.